can some one explain exactly why you need a sub sonic filter on when you have a sub in a ported box. What exactly will happen to the sub if the filter is not on? why does it do this? Please explain the mechanics and stuff about it. Thanks.
Below tuning, the subwoofer "unloads" from the box, performing as if the box wasn't there b/c the air in the port can't control the cone. This equates to extreme excursion (possibly overexcursion) and if you don't run a subsonic filter, it could result in mechanical damage to the subwoofer.
I have 2 V-Max's and a Sony 1200w amp, in a 4.3 cubic foot box with 1 inch of insulation on each sides tuned to 33 Hz, do i need a filter, my amp already has a low pass set on 110 Hz?
Juggalo Jeff
Unregistered guest
Posted on
alright ya'll i have 2 10" alpine type r's in a q logic box which can be sealed or ported right now it is ported and the port tubes are to specification 12" inches each my amp has a subsonic filter on it but the level is all the way down are my subs being hurt at all and how do u kno what ur tuning is at
Steven, a subsonic could probably help you, I'd go w/ about 25 hz.
Juggalo Jeff, depends on what the box is tuned at. 5-10 hz below the tuned frequency usually works well. Better safe than sorry, hard to say whether they're stressed mechanically or not (or ever will be) but as they say "an ounce of prevention is worth a pound of cure".
Steven, it could possibly if you're having trouble at really low (below say 25 hz) bass tones and your sub is bottoming out at loud levels, but very little music gets that low, so w/ most songs you probably wouldn't notice a difference. The amp will have more power since it isn't having to produce those tones as loudly (subsonics take a LOT of power). But of course, that only applies when the music has that signal on it. Basically, it's more for prevention than it is for sound.
Juggalo, it depends on the size of the enclosure, surface area of the port and port length. Also depends on the subs displacement.
Juggalo Jeff
Unregistered guest
Posted on
well i just have a q logic box with 2 10" alpine type r's(1041d) it is ported right now the tubes are both 12 inches right now which is what the sub calls for and the diameter is 3 inches maybe 4. I believe the box volume is 1.0 cu. ft for each sub
I don't know if that 1.0 cu ft volume is net or gross, but you're best off giving me the internal dimensions of the box for each subwoofer. Also, make sure what diameter the port is, an inch diameter makes a huge difference in tuning frequency.
Ok, found your box on Crutchfield. I trust Fishy, and the fact that most prefabs are in high 30s and 40s anyway. That box uses 3" ports, so your tuning is in the high 30s. Subsonic of about 30 hz will work.
I gave you a reasonable margin, high 30s was all I expected of you ;).
Juggalo Jeff
Unregistered guest
Posted on
yea thats what it is i just have a power acoustik amp and it has the sub sonic filter on it just the dial it goes from 30 hz to 175 hz and i got it all the way down on 30 hz so this is fine right
